<template>
    <div class='xtx-carousel' @mouseenter="stop" @mouseleave="start">
        <!-- 轮播图片容器 -->
        <ul class="carousel-body">
            <!-- fade 显示的图片加上 -->
            <li class="carousel-item" v-for="(item, i) in sliders" :key="i" :class="{ fade: index === i }">
                <!-- 轮播图 -->
                <RouterLink v-if="item.imgUrl" to="/">
                    <img :src="item.imgUrl" alt="">
                </RouterLink>
                <!-- 轮播商品 -->
                <div v-else class="slider">
                    <RouterLink v-for="goods in item" :key="goods.id" :to="`/product/${goods.id}`">
                        <img :src="goods.picture" alt="">
                        <p class="name ellipsis">{{ goods.name }}</p>
                        <p class="price">&yen;{{ goods.price }}</p>
                    </RouterLink>
                </div>
            </li>
        </ul>
        <!-- 上一页 -->
        <a @click="toggle(-1)" href="javascript:;" class="carousel-btn prev"><i
                class="iconfont icon-angle-left"></i></a>
        <!-- 下一页 -->
        <a @click="toggle(1)" href="javascript:;" class="carousel-btn next"><i
                class="iconfont icon-angle-right"></i></a>
        <!-- 指示器 -->
        <div class="carousel-indicator">
            <!-- active 激活当前的小圆点 -->
            <span @click="index = i" v-for="(item, i) in sliders" :key="i" :class="{ active: index === i }"></span>
        </div>
    </div>
</template>

<script>
import { ref, watch, onUnmounted } from 'vue'
export default {
    name: 'XtxCarousel',
    props: {
        sliders: {
            type: Array,
            default: []
        },
        // 是否开启轮播效果
        autoPlay: {
            type: Boolean,
            default: false
        },
        // 间隔时间
        duration: {
            type: Number,
            default: 3000
        }
    },
    setup(props) {
        let index = ref(0)

        let timer = null
        function autoPlayFn() {
            // 开启定时器之前 清除原先的定时器
            clearInterval(timer)
            timer = setInterval(() => {
                index.value++
                if (index.value >= props.sliders.length) {
                    index.value = 0
                }
            }, props.duration)
        }
        //监听定时器启动的条件
        watch(() => props.sliders, (newValue) => {
            if (newValue.length && props.autoPlay) {
                autoPlayFn()
            }
        }, { immediate: true })

        //鼠标进入暂停 鼠标离开启动
        const stop = () => {
            if (timer) clearInterval(timer)
        }
        const start = () => {
            clearInterval(timer)
            if (props.sliders.length && props.autoPlay) {
                autoPlayFn()
            }
        }

        // 点击上下页轮播
        const toggle = (data) => {
            index.value = index.value + data
            if (index.value >= props.sliders.length) {
                index.value = 0
            } else if (index.value < 0) {
                index.value = props.sliders.length - 1
            }
        }


        //组件卸载  清除定时器
        onUnmounted(() => {
            clearInterval(timer)
        })

        return {
            index,
            stop,
            start,
            toggle
        }
    }

}
</script>
<style scoped lang="less">
.xtx-carousel {
    width: 100%;
    height: 100%;
    min-width: 300px;
    min-height: 150px;
    position: relative;

    .carousel {
        &-body {
            width: 100%;
            height: 100%;
        }

        &-item {
            width: 100%;
            height: 100%;
            position: absolute;
            left: 0;
            top: 0;
            opacity: 0;
            transition: opacity 0.5s linear;

            &.fade {
                opacity: 1;
                z-index: 1;
            }

            img {
                width: 100%;
                height: 100%;
            }
        }

        &-indicator {
            position: absolute;
            left: 0;
            bottom: 20px;
            z-index: 2;
            width: 100%;
            text-align: center;

            span {
                display: inline-block;
                width: 12px;
                height: 12px;
                background: rgba(0, 0, 0, 0.2);
                border-radius: 50%;
                cursor: pointer;

                ~span {
                    margin-left: 12px;
                }

                &.active {
                    background: #fff;
                }
            }
        }

        &-btn {
            width: 44px;
            height: 44px;
            background: rgba(0, 0, 0, .2);
            color: #fff;
            border-radius: 50%;
            position: absolute;
            top: 228px;
            z-index: 2;
            text-align: center;
            line-height: 44px;
            opacity: 0;
            transition: all 0.5s;

            &.prev {
                left: 20px;
            }

            &.next {
                right: 20px;
            }
        }
    }

    &:hover {
        .carousel-btn {
            opacity: 1;
        }
    }
}
// 轮播商品
.slider {
  display: flex;
  justify-content: space-around;
  padding: 0 40px;
  > a {
    width: 240px;
    text-align: center;
    img {
      padding: 20px;
      width: 230px!important;
      height: 230px!important;
    }
    .name {
      font-size: 16px;
      color: #666;
      padding: 0 40px;
    }
    .price {
      font-size: 16px;
      color: @priceColor;
      margin-top: 15px;
    }
  }
}

</style>
